Compact 5-Band Multimode QRP Kits by PE1NNZ and DL2MAN

Thanks to the contributions of DL2MAN and PE2NNZ, we are certified by the original creators. The (tr)uSDX is the successor of the uSDX Project, resulting from the collaboration between PE1NNZ and DL2MAN. The design was intended as an easy-to-build (pre-assembled) kit.

The (tr)uSDX is supplied with an OLED display, an onboard microphone, a (tiny) onboard speaker, and a PTT key that can be used as an emergency CW key for improvised QSOs. It also includes an onboard SWR bridge and voltage/current measurement hardware to assist in tuning and operation.

For the LO kits, no case is provided, and the user needs to assemble it themselves. The kit covers the 5-band frequencies of 80/60/40/30/20m.

To reprogram or upgrade the firmware (or program your callsign to the firmware), follow these steps:

1. Download the firmware from DL2MAN's page.
2. Enter the serial number (found in the package) and download the firmware.
3. Install the USB driver for the CH340 driver and AVR-Dudess software. If the computer prompts that the AVR-Dudess cannot be installed, try using another computer.
4. Restart the computer and use a USB cable to connect the mainboard. The computer should make a "ding-dong" sound, indicating that the CH340 driver software has been installed successfully. If not, try using another USB data cable.
5. Open the AVR-Dudess software and program the firmware, following the instructions in the picture.

To use the RESET function, follow these steps:

1. Hold down the encoder (do not release your hand) and turn on the power.
2. After the "restart" message appears on the OLED, release your hand.

The mainboard has been burned with the bootloader and programmed with the firmware. You need to program the callsign yourself by entering the serial number, which is provided in the package.

Good news: an orange assembled rig is available, which can be plugged in and played. Search for "tr usdx" on another page.

The (tr)uSDX has a (micro)USB CAT and programming interface, and while it typically produces 5W @ 13.8V power supply, it can create 0.5W output from a 5V USB supply alone.

product information: